While early April mayfly hatches are few and far between, the season usually opens with a hatch of small, black stoneflies already underway. For the first two weeks, the successful flyfisher often fishes wet,.using nymphs, stoneflies or streamers. By the third week of April, the mayflies begin to emerge. The first to arrive are Blue Quills (16. 18), Blue Wing Olives (14, 16) ,  and Quill Gordons (12, 14). By the end of the month, you can expect to see Light Hendricksons (12) and Dark Hendricksons (12, 14). For those who fish nymphs, try a Gold Ribbed Hare's Ear, or a Pheasant Tail Nymph. These are nymph standards throughout the season, and are often fished with a bead head for a deeper drift. Sizes 12 to 20. Wooly Buggers, Zonkers and Alewive streamers are also productive, as are wet flies like the Slate-winged Coachman and the Zug Bug.

May:

There's a reason they call them "mayflies" and the month of May is it.   This is the start of a mayfly smorgasbord that includes all of the mid to late-April arrivals -- Blue Quills (16, 18), Blue Wing Olives (14, 16), Quill Gordons and Light and Dark Hendricksons (12, 14) -- and a mid-month blizzard of March Browns (12), Gray Fox (12, 14), Green Drakes (10) and Brown Drakes (12).   There's also a smattering of the light flies, including sulphurs (E. Dorotheas) (16, 18), Light Cahills (14) and Pale Evening Duns (14).  Several of the mid- to late May hatches spill over into early June, when the sulphur group  begins to come on strong. Nymphs, emergers, and spinners to match the phases of each hatch are essential for the complete flyfisher, and can be the flies of choice depending on time of day and conditions.  The season-long standard nymphs -- Gold Ribbed Hare's Ear and Pheasant Tails -- are also productive.

June:

There's hardly a mayfly that doesn't take flight in June, although several are limited to the first couple of weeks. The Green Drake (10), Brown Drake (12) and Gray Fox (12, 14) may all be present in the first week or two,  and both light- and dark-bodied Blue-wing olives ( 14, 16) (cornutas and cornutellas). In mid- to late June, the Sulphurs (16, 18), Light and Dark Cahills (14) and Pale Evening Duns (14) come on strong, while Isonychia (12) begin to show sporadically and Yellow Drakes (12) start up. Finally, the little bugs of summer start to show in late June, with morning hatches of black-and-white tricos (22, 24) and afternoon hatches of pseudocloeons, or tiny blue-winged olives (22-24). Nymphs, emergers and spinners to cover the phases of each of the mayflies should be included in your fly box, too. Also, don't forget the nymph standards -- gold-ribbed hare's ear and pheasant tails -- and remember that streamers continue to be productive in early morning and evening.

July:

The days of summer are among the most challenging of the flyfisher's year, usually because the fishing is fine and the trout are especially finicky. A trout's breakfast is typically composed of tricos (tricorythodes) (22, 24) while the evening dish might be tiny blue-winged olives (pseduocloeons) (22 -24). In the afternoon, there can be big hatches of blue-winged olives (cornutas and cornutellas) (14, 16), sulphurs (16, 18) and the occasional Isonychia (12). During the magic hour -- from twilight to dark -- look for all the above flies, plus some Light Cahills (14) and Pale Evening Duns (14, 16). The warm summer months also offers the flyfisher a new challenge: terrestrials. Ants (16-22), beetles (16-20) and grasshoppers (12, 14 long) can provide great sport and produce big fish from late morning through the afternoon. Day-time fishing can be productive with nymphs, and early and late-hour angling with streamers can also lead to a big brown or rainbow. Pheasant Tails and Wooly Buggers are good standards.

August:

Even though there's nothing new on the water, August can be one of the best and most challenging months for the flyfisher. There's trout sipping in the early morning and late evening. They're usually rising for tricos (22, 24) and tiny blue-winged olives (pseudocloeons) (22-24). And, during the day you can sometimes pound up a trout with an Isonychia (12) or attractor pattern fished dead-drift through the riffles. There's always the chance of a mid-day hatch of cornutas, blue-winged olives (14, 16), and gray caddis (14, 16, 18) can also be productive. Sulphurs (14-20) are also present, along with Light Cahills (14) and Pale Evening Duns (14, 16). The Golden Hour at the end of the day is usually celebrated by highly selective rising trout, who dimple the river's waters steadily. Figuring out exactly what is on the dinner menu can be a challenge. During the day, you can go after the big ones on top with an assortment of artificial ants, beetles and grasshoppers in various sizes, colors and patterns. Pheasant tail nymphs fished along the bottom can produce some big trout, along with streamers in the early mornings and evenings,

September:

With cool nights and warm days, September can be one of the most productive and enjoyable months of the season, both for the three rivers that make up the Upper Delaware system and the Beaverkill and Willowemoc, which are reborn after the hot months of summer. Blue-winged olives (pseudocloeons) (20-24) are still coming off the rivers in the afternoons and evenings, and tricos (22-24) continue to hatch in the larger pools and slow waters, usually to a host of sipping trout. There's also some lingering sulphurs (16-20), which can produce some good spinner falls in the evening. Tan caddis (14, 16) and gray caddis (16) also offer some top-water action... In addition, Isonychia (12) begin to appear regularly on the big water of the Delaware, along with some late-season stoneflies. This is a time of year when big trout can be pounded up with stimulators and attractors floated through the riffles and rapids. Mymphs and streamers continue to score.

October: